Local air conditioning apparatus

ABSTRACT

A local air conditioning apparatus for installations with distribution of secondary water through four pipes, comprising two heat-exchangers housed in two different chambers with an interposed neutral or by-pass chamber, and a fan for conveying the air to be conditioned through one or two of said chambers, said fan being rotatable so that its outlet can be adjusted in a stepless way to correspond with the inlet of one of the chambers or bridging the inlet of two adjacent chambers.

United States Patent 1 Serratto 51 Jan; 2, 1973 [54] LOCAL AIR CONDITIONING APPARATUS [76] Inventor:

Milan, ltaly [22] Filed: Dec. 10, 1970 [2l] Appl. No.: 96,784

[30] Foreign Application Priority Data Dec. 24, 1969 ltaly ..26302l Al 69 [52] U.S.Cl. ..l65/22,l65/48,165/50,

[51] Int. Cl. ..F24f3/00 [58] FieldoiSearch ..l65/22,26,48,l26,l22

Angelo Serratto, Piazza Novelli 10,.

[56] References Cited UNITED STATES PATENTS 2,894,728 7/1959 Davis ..l65/l26 Primary Examiner-Charles Sukalo AttorneyBrowdy & Neimark [57] ABSTRACT A local air conditioning apparatus for installations with distribution of secondary water through four pipes, comprising two heat-exchangers housed in two different chambers with an interposed neutral or bypass chamber, and a fan for conveying the air to be conditioned through one or two of said chambers, said fan being rotatable so that its outlet can be adjusted in a stepless way to correspond with the inlet of one of the chambers or bridging the inlet of two adjacent chambers.

' 7 Claims, 3 Drawing Figures LOCAL AIR CONDITIONING APPARATUS BACKGROUND OF THE INVENTION This inventionrelates to a local air conditioning apparatus for air conditioning installations constructed according to the convector-fan system with secondary water distribution through four pipes.

Air conditioning installations are known, in which, contrary to centralized air conditioning installations where all the air is conditioned in one single space the air is conditioned in the decentralized spaces of the individual air conditioned rooms. This is made possible by adopting a large number of localair conditioning apparatus, part or none of the conditioning operations being performed centrally and the remaining part thereof being performed directly in the rooms, in accordance with the control and adjustment requirements of the room conditions. Obviously, the more the air conditioning system is decentralized, the better it is possible to adjust the different characteristic factors which vary from one room to another, but generally the cost of the installation rises in proportion to the decentralization of the air conditioning apparatus.

The known local air conditioning apparatus consists of a wooden or metal housing including one heatexchanger fed with hot or cold water, which exchanges the heat with the air passing therethrough under the effect of a fan, included in the same housing, which from here conveys hot or cold air into the room to be heated or cooled respectively. In such known local apparatus, the room temperature can be varied either by modifying the quantity of water flowing through the coils of the heat-exchanger and/or by modifying the air capacity of the fan by acting upon the speed of revolution of the fan.

There are also known local convector-fan apparatus comprising two heat-exchangers laid out in series which are alternatively fed with hot or cooled water, each of these heat-exchangers being connected to a flow and back-flow pipe, thus forming the system known under the name of four-pipe-system. Also in this type of local apparatus the temperature in the room can be varied by varying the quantity of hot or cold water which feeds the one or the other of the two heat-exchangers.

The known air conditioning installations wherein the adjustment of the room temperature can be effected by varying the quantity of secondary water circulating in the heat-exchangers have many disadvantages such as great thermal inertia. of the local apparatus, difficult control of the actual watertightness of the regulation valves; high maintenance costs, the possibility of hot water mixing with cooled water in return piping and consequent increase in operationalcosts, etc.

SUMMARY OF THE DISCLOSURE It is therefore the main-object of this invention to provide a local air conditioning apparatus for. a fourpipe system wherein the adjustment of the room temperature can be effected without varying the quantity of secondary water circulating in the heat-exchangers.

Another object of the invention is to provide a local air conditioning apparatus for a four-pipe system wherein the room temperature can be adjusted by varying the quantity of air which flows through the heatexchangers.

A further object of the invention is to provide a local air conditioning apparatus which permits, in each room of a building provided with a four-pipe air conditioning system, a flexible, fast and efficient temperature adjustment with a very simple working and a considerable reduction in costs.

These and other objects are attained by providing a local air conditioning apparatus comprising two heatexchangers and a fan which pushes the air to be conditioned through the heat-exchangers, which are simultaneously fed, the one with cooling fluid and the other with heating fluid, andare housed respectively in two different chambers with an interposed neutral or bypass chamber, and in that the fan has a housing which is shaped so that when the fan outlet is exactly in correspondence of the inlet of one of the three chambers, it closes the inlet of the other chambers, the fan being rotatable so that its outlet can be adjusted in a stepless way to correspond with the inlet of each of the three chambers or bridging two adjacent chambers.

The local air conditioning apparatus according to the present invention has the main advantage that its flexibility in working is such that in the same conditioned building, some rooms may be cooled while others are heated.

Another advantage of apparatus of the present invention is that its low cost and high efficiency are achieved by avoiding also the presence of passive induced fluid currents in the inactive sections.

Further advantages, objects and characteristics of the air conditioning apparatus according to this invention will be evident from the following detailed description of an embodiment thereof given by way of nonlimiting example with reference to the accompanying drawings, wherein:

FIG. 1 shows a diagram of a complete air conditioning system in a multicellular building provided with a local air conditioning apparatus according to this invention;

FIG. 2 shows a diagrammatic front-view, partly in section, of the local air conditioning apparatus according to this invention; and

FIG. 3 shows a section-view taken along the line A- A of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to FIG. 1, there can be seen a cooler l, which cools the cooling fluid, generally water, circulated by means of pump 2. On the other hand, the heating fluid; generally water, which is circulated by means of pump 4, is heated in the generator 3. In the diagram of the system the full line indicates the circuit of the cooling fluid while the dashed line indicates the circuit of the heating fluid. For each room to be air-conditioned, there can be seen diagrammatically how each local apparatus 5 is connected in parallel to the four pipes of the secondary water distribution.

FIGS. 2 and 3 show more in detail an embodiment of the convector-fan apparatus 5 which is the object of this invention. The air to be conditioned, which may be either exclusively air from the room where the apparatus is installed, or a mixture of ambient air and air taken from outside, enters the apparatus 5 through slots 6 and is filtered through the filter 7.

Once it is thus filtered, the air is sucked off by the fan shown as a centrifugal fan 8, with the fan-wheel 9 and the motor 10. In this embodiment the motor 10 is connected directly to the fan-wheel by the shaft 11, but they can generally be coupled by means of an appropriate gear means. The air-throw outlet 12 of the fan 8 is integral with a housing 13 rotatable around the axle X-X. The housing 13 is opened at its lower part between the generatrixes l4 and 15, in order to make it possible for the air which has crossed the filter 7 to reach the fan system by suction. The whole remaining full surface of the housing 13 is closed except for the slot or slots provided in front of the outlet 12 of the fan 8. Said slot or slots are positioned on the housing surface so that by rotating the housing they can be in a stepless way brought to correspond with the inlets of the chambers 23, 24 and 25, or bridging two adjacent chambers. The motor 10 is supported by a cross-piece 16 with the aid of an elastic cradle 17. In FIG. 2, there has been shown an electric motor 10, but the latter may be indifferently a hydraulic engine or any other type of engine. It should be remembered that the cross-piece 16 may be abolished and that the motor 10 may be mounted directly onto the housing 13.

Bothvthe housing and the cross-piece 16 are supported by two disks 18 which are free to rotate around the axle X--X embodied by the two pivots 19 housed in the bearings 20 and supported by the lateral supporting and base plates 21, which in turn rest on the floor through the adjustable screws 22.

In the illustrated embodiment, a convector-fan system adapted to rest on the floor has been represented. Of course, the apparatus may also be designed to hang vertically from a wall, or horizontally from the ceiling. The fact of fixing the housing 13 and through cross-piece 16 the motor 10 to the two disks 18 makes it possible to cause the whole system composed by the housing 13, the fan 8 with the wheel 9 and the motor 10 to rotate around the axle XX, thus directing the flow of air coming from the outlet 12 into the chambers 23,24 or 25, or in any intermediate position. In FIG. 3, the flow of air totally enters the chamber 23 so that all the air sucked off by the fan 8 will have to pass before coming out from the outlet 26 through the exchanger 27 crossed by the cooling fluid coming from the refrigerator 1 and circulated by pump 2.

The cooling chamber 23 is separated from the neutral or by-pass chamber 24 by a baffle-plate 29 ending at its lower part by the condensate water trap 31, while the battle-plate 30 separates the by-pass chamber 24 from the heating chamber 25, the exchanger 28 being crossed bythe heating fluid coming from the generator 3 and circulated by the pump 4.

The outlet 12 of the fan is positioned in FIG. 3 in such a way as to confer to the apparatus 5 the maximum cooling capacity, while the chambers 24 and 25 are closed at their lower part by the housing surface extending at the right hand side of the air-throw outlet 12.

When the whole housing-fan-motor is rotated clockwise around the axle X-X, the flow of air coming I from the outlet 12 will more and more enter into the by-pass chamber 24 and less and less into the cooling chamber 23 and, as rotation goes on, only into the chamber 24 and subsequently both into the chamber 24 and the heating chamber 25 and finally, at the end of said rotation, only into the chamber 25 so that the apparatus will supply the maximum heating capacity, since the whole flow of air will cross the heating exchanger 28. In this position, the chambers 23 and 24 are closed by the housing surface extending at theleft hand side of outlet 12. In the mixing chamber 32, the flows of air coming either from the exchanger 27 and the by-pass 24, or from said by-pass 24 and the exchanger 28 are mixed together before coming out from the outlet 26.

The baffle-plates 29 and 30, the two side-walls 33 to which the latter is connected, the water trap 31, the two vertical panels 34 and 35 and the two upper panels 36 and 37 delimit, together with the two exchangers 27 and 28, the cooling chamber 23, the by-pass chamber 24, the heating chamber. 25 and the mixing chamber 32. Moreover, these chambers are delimited at their lower part, besides the baffle-plates 29. and 30, by the housing 13 and two longitudinal side-members 38 and 39 which contribute to avoid induced currents in the inactive chambers, thus reducing passive losses to a minimum and improving the efficiency of the apcase, the two side-walls 33 and the two heat-exchangers 27 and 28 can be designed so as to permit an easy inversion of the hydraulic connections, even during the installation. The upper connection is preferably provided with an air exhaust device 41 and the water trap 31 is provided with two drains 42 on each side of the apparatus: the drain which is not in service is closed by a plastic cap.

The apparatus illustrated in FIGS. 2 and 3 is a basic unit for a vertical arrangement. If a horizontal arrangement is required, the cooling exchanger 27 will have to be housed in the lower part of the apparatus and the panel 34 will have to be replaced by a condensate water trap. In the illustrated embodiment the motor operates only one fan-wheel, but in some other cases the motor may operate two fan-wheels through one single gear shaft projecting from both ends of the motor, so that the fan-wheels are arranged symmetrically with respect to a median plane perpendicular to the axis of the motor. The adoption of one or two fan-wheels and, accordingly, of one or two fans, will substantially depend on the air-capacity of the fan-convector. Fans of other kinds can be-also used for some diflerent embodiments of the present invention.

Although the invention has been described in considerable detail with reference to certain preferred embodiments thereof, it will be understood that variations and modifications can be effected within the spirit and scope of the invention as described and defined in the appended claims.

What is claimed is:

1. A local air conditioning apparatus for installations with a four-pipe system comprising a casing and two heat exchangers within said casing, each exchanger being associated with two of said pipes, the improvement comprising:

baffle means within said casing for defining a separate chamber within said casing for each of said heat exchangers and for defining a third chamber therebetween;

fan means within said casing for forcing air toward said heat exchangers, said fan means having a housing therearound; and

means connected to said casing for controlling the direction of air flow from said fan means solely into any one of said three chambers or partly into two adjacent chambers, said means comprising an outlet opening in said housing, an axle supported by said casing, said housing being rotatably mounted on said axle, whereby upon rotation of said housing about said axle said outlet opening of said housing is in air flow alignment with one of said chambers or partially bridging two of said adjacent chambers.

2. A local air conditioning apparatus according to claim 1 wherein said fan means comprises a centrifugal fan.

3. A local air conditioning apparatus according to claim 1 wherein said fan means is integrally connected with said housing.

4. A local air conditioning apparatus according to claim 3 wherein said fan means includes a fan and a driving means for said fan and wherein'said driving means is mounted inside said housing.

5. A local air conditioning apparatus according to claim 1 further including rotating means connected to said housing for rotating said housing.

6. A local air conditioning apparatus according to claim 5 further including means, connected to said rotating means, for controlling the position of said housing outlet opening as a function of ambient temperature.

7. A local air conditioning apparatus for installations with a four-pipe system, comprising a metal case, two heat-exchangers within said case laid out in parallel and mounted in two separate chambers which define a bypass chamber therebetween, a fan adapted to push air through the heat-exchangers by means of an adjustable outlet, said fan having a motor means and a housing providedwith passages for the inlet and the outlet of the air, the outlet passage being placed in correspondence with the fan outlet and integral thereto and having an outlet cross-section coextensive in width with the inlet of at most one of said three chambers, an axle supported by said metal case, said fan housing being rotatably mounted on said axle, each of said chambers of the heat-exchangers being defined by a plurality of fixed walls comprising portions of said metal case, the same heat-exchanger and one of a pair of baffle plates, and by a movable wall which is said fan housing, and said bypass chamber being defined by said pair of baffle plates and the same fan housing, two longitudinal side members being provided for preventing induced currents from entering said bypass chamber, whereby when the fan housing outlet is in correspondence with one of 5 id three hambers, the'inlet of the other chambers 18 c osed an at the most the housing outlet is adapted to bridge partially two adjacent chambers. 

1. A local air conditioning apparatus for installations with a four-pipe system comprising a casing and two heat exchangers within said casing, each exchanger being associated with two of said pipes, the improvement comprising: baffle means within said casing for defining a separate chamber within said casing for each of said heat exchangers and for defining a third chamber therebetween; fan means within said casing for forcing air toward said heat exchangers, said fan means having a housing therearound; and means connected to said casing for controlling the direction of air flow from said fan means solely into any one of said three chambers or partly into two adjacent chambers, said means comprising an outlet opening in said housing, an axle supported by said casing, said housing being rotatably mounted on said axle, whereby upon rotation of said housing about said axle said outlet opening of said housing is in air flow alignment with one of said chambers or partially bridging two of said adjacent chambers.
 2. A local air conditioning apparatus according to claim 1 wherein said fan means comprises a centrifugal fan.
 3. A local air conditioning apparatus according to claim 1 wherein said fan means is integrally connected with said housing.
 4. A local air conditioning apparatus according to claim 3 wherein said fan means includes a fan and a driving means for said fan and wherein said driving means is mounted inside said housing.
 5. A local air conditioning apparatus according to claim 1 further including rotating means connected to said housing for rotating said housing.
 6. A local air conditioning apparatus according to claim 5 further including means, connected to said rotating means, for controlling the position of said housing outlet opening as a function of ambient temperature.
 7. A local air conditioning apparatus for installations with a four-pipe system, comprising a metal case, two heat-exchangers within said case laid out in parallel and mounted in two separate chambers which define a bypass chamber therebetween, a fan adapted to push air through the heat-exchangers by means of an adjustable outlet, saId fan having a motor means and a housing provided with passages for the inlet and the outlet of the air, the outlet passage being placed in correspondence with the fan outlet and integral thereto and having an outlet cross-section coextensive in width with the inlet of at most one of said three chambers, an axle supported by said metal case, said fan housing being rotatably mounted on said axle, each of said chambers of the heat-exchangers being defined by a plurality of fixed walls comprising portions of said metal case, the same heat-exchanger and one of a pair of baffle plates, and by a movable wall which is said fan housing, and said bypass chamber being defined by said pair of baffle plates and the same fan housing, two longitudinal side members being provided for preventing induced currents from entering said bypass chamber, whereby when the fan housing outlet is in correspondence with one of said three chambers, the inlet of the other chambers is closed and at the most the housing outlet is adapted to bridge partially two adjacent chambers. 